part fix for issue #3: remove and ignore summaries.dat
fuel: convert menu to use characters instead of numbers. include `edit_record` stub. doc strings
final fix for issue #3: summaries generated on the fly. new `get_summary` retrieve records, or calls `summary` to create one. `summary` also edits/update existing records instead of just appedning them. `graph` and `predict` use `get_summary` now